diff options
Diffstat (limited to 'arch/ia64/kernel/ptrace.c')
| -rw-r--r-- | arch/ia64/kernel/ptrace.c | 1627 |
1 files changed, 1627 insertions, 0 deletions
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c new file mode 100644 index 000000000000..55789fcd7210 --- /dev/null +++ b/arch/ia64/kernel/ptrace.c @@ -0,0 +1,1627 @@ +/* + * Kernel support for the ptrace() and syscall tracing interfaces. + * + * Copyright (C) 1999-2005 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + * + * Derived from the x86 and Alpha versions. + */ +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/smp_lock.h> +#include <linux/user.h> +#include <linux/security.h> +#include <linux/audit.h> + +#include <asm/pgtable.h> +#include <asm/processor.h> +#include <asm/ptrace_offsets.h> +#include <asm/rse.h> +#include <asm/system.h> +#include <asm/uaccess.h> +#include <asm/unwind.h> +#ifdef CONFIG_PERFMON +#include <asm/perfmon.h> +#endif + +#include "entry.h" + +/* + * Bits in the PSR that we allow ptrace() to change: + * be, up, ac, mfl, mfh (the user mask; five bits total) + * db (debug breakpoint fault; one bit) + * id (instruction debug fault disable; one bit) + * dd (data debug fault disable; one bit) + * ri (restart instruction; two bits) + * is (instruction set; one bit) + */ +#define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS \ + | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI) + +#define MASK(nbits) ((1UL << (nbits)) - 1) /* mask with NBITS bits set */ +#define PFM_MASK MASK(38) + +#define PTRACE_DEBUG 0 + +#if PTRACE_DEBUG +# define dprintk(format...) printk(format) +# define inline +#else +# define dprintk(format...) +#endif + +/* Return TRUE if PT was created due to kernel-entry via a system-call. */ + +static inline int +in_syscall (struct pt_regs *pt) +{ + return (long) pt->cr_ifs >= 0; +} + +/* + * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT + * bitset where bit i is set iff the NaT bit of register i is set. + */ +unsigned long +ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat) +{ +# define GET_BITS(first, last, unat) \ + ({ \ + unsigned long bit = ia64_unat_pos(&pt->r##first); \ + unsigned long nbits = (last - first + 1); \ + unsigned long mask = MASK(nbits) << first; \ + unsigned long dist; \ + if (bit < first) \ + dist = 64 + bit - first; \ + else \ + dist = bit - first; \ + ia64_rotr(unat, dist) & mask; \ + }) + unsigned long val; + + /* + * Registers that are stored consecutively in struct pt_regs + * can be handled in parallel. If the register order in + * struct_pt_regs changes, this code MUST be updated. + */ + val = GET_BITS( 1, 1, scratch_unat); + val |= GET_BITS( 2, 3, scratch_unat); + val |= GET_BITS(12, 13, scratch_unat); + val |= GET_BITS(14, 14, scratch_unat); + val |= GET_BITS(15, 15, scratch_unat); + val |= GET_BITS( 8, 11, scratch_unat); + val |= GET_BITS(16, 31, scratch_unat); + return val; + +# undef GET_BITS +} + +/* + * Set the NaT bits for the scratch registers according to NAT and + * return the resulting unat (assuming the scratch registers are + * stored in PT). + */ +unsigned long +ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat) +{ +# define PUT_BITS(first, last, nat) \ + ({ \ + unsigned long bit = ia64_unat_pos(&pt->r##first); \ + unsigned long nbits = (last - first + 1); \ + unsigned long mask = MASK(nbits) << first; \ + long dist; \ + if (bit < first) \ + dist = 64 + bit - first; \ + else \ + dist = bit - first; \ + ia64_rotl(nat & mask, dist); \ + }) + unsigned long scratch_unat; + + /* + * Registers that are stored consecutively in struct pt_regs + * can be handled in parallel. If the register order in + * struct_pt_regs changes, this code MUST be updated. + */ + scratch_unat = PUT_BITS( 1, 1, nat); + scratch_unat |= PUT_BITS( 2, 3, nat); + scratch_unat |= PUT_BITS(12, 13, nat); + scratch_unat |= PUT_BITS(14, 14, nat); + scratch_unat |= PUT_BITS(15, 15, nat); + scratch_unat |= PUT_BITS( 8, 11, nat); + scratch_unat |= PUT_BITS(16, 31, nat); + + return scratch_unat; + +# undef PUT_BITS +} + +#define IA64_MLX_TEMPLATE 0x2 +#define IA64_MOVL_OPCODE 6 + +void +ia64_increment_ip (struct pt_regs *regs) +{ + unsigned long w0, ri = ia64_psr(regs)->ri + 1; + + if (ri > 2) { + ri = 0; + regs->cr_iip += 16; + } else if (ri == 2) { + get_user(w0, (char __user *) regs->cr_iip + 0); + if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) { + /* + * rfi'ing to slot 2 of an MLX bundle causes + * an illegal operation fault. We don't want + * that to happen... + */ + ri = 0; + regs->cr_iip += 16; + } + } + ia64_psr(regs)->ri = ri; +} + +void +ia64_decrement_ip (struct pt_regs *regs) +{ + unsigned long w0, ri = ia64_psr(regs)->ri - 1; + + if (ia64_psr(regs)->ri == 0) { + regs->cr_iip -= 16; + ri = 2; + get_user(w0, (char __user *) regs->cr_iip + 0); + if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) { + /* + * rfi'ing to slot 2 of an MLX bundle causes + * an illegal operation fault. We don't want + * that to happen... + */ + ri = 1; + } + } + ia64_psr(regs)->ri = ri; +} + +/* + * This routine is used to read an rnat bits that are stored on the + * kernel backing store. Since, in general, the alignment of the user + * and kernel are different, this is not completely trivial. In + * essence, we need to construct the user RNAT based on up to two + * kernel RNAT values and/or the RNAT value saved in the child's + * pt_regs. + * + * user rbs + * + * +--------+ <-- lowest address + * | slot62 | + * +--------+ + * | rnat | 0x....1f8 + * +--------+ + * | slot00 | \ + * +--------+ | + * | slot01 | > child_regs->ar_rnat + * +--------+ | + * | slot02 | / kernel rbs + * +--------+ +--------+ + * <- child_regs->ar_bspstore | slot61 | <-- krbs + * +- - - - + +--------+ + * | slot62 | + * +- - - - + +--------+ + * | rnat | + * +- - - - + +--------+ + * vrnat | slot00 | + * +- - - - + +--------+ + * = = + * +--------+ + * | slot00 | \ + * +--------+ | + * | slot01 | > child_stack->ar_rnat + * +--------+ | + * | slot02 | / + * +--------+ + * <--- child_stack->ar_bspstore + * + * The way to think of this code is as follows: bit 0 in the user rnat + * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat + * value. The kernel rnat value holding this bit is stored in + * variable rnat0. rnat1 is loaded with the kernel rnat value that + * form the upper bits of the user rnat value. + * + * Boundary cases: + * + * o when reading the rnat "below" the first rnat slot on the kernel + * backing store, rnat0/rnat1 are set to 0 and the low order bits are + * merged in from pt->ar_rnat. + * + * o when reading the rnat "above" the last rnat slot on the kernel + * backing store, rnat0/rnat1 gets its value from sw->ar_rnat. + */ +static unsigned long +get_rnat (struct task_struct *task, struct switch_stack *sw, + unsigned long *krbs, unsigned long *urnat_addr, + unsigned long *urbs_end) +{ + unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr; + unsigned long umask = 0, mask, m; + unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift; + long num_regs, nbits; + struct pt_regs *pt; + + pt = ia64_task_regs(task); + kbsp = (unsigned long *) sw->ar_bspstore; + ubspstore = (unsigned long *) pt->ar_bspstore; + + if (urbs_end < urnat_addr) + nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end); + else + nbits = 63; + mask = MASK(nbits); + /* + * First, figure out which bit number slot 0 in user-land maps + * to in the kernel rnat. Do this by figuring out how many + * register slots we're beyond the user's backingstore and + * then computing the equivalent address in kernel space. + */ + num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1); + slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs); + shift = ia64_rse_slot_num(slot0_kaddr); + rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr); + rnat0_kaddr = rnat1_kaddr - 64; + + if (ubspstore + 63 > urnat_addr) { + /* some bits need to be merged in from pt->ar_rnat */ + umask = MASK(ia64_rse_slot_num(ubspstore)) & mask; + urnat = (pt->ar_rnat & umask); + mask &= ~umask; + if (!mask) + return urnat; + } + + m = mask << shift; + if (rnat0_kaddr >= kbsp) + rnat0 = sw->ar_rnat; + else if (rnat0_kaddr > krbs) + rnat0 = *rnat0_kaddr; + urnat |= (rnat0 & m) >> shift; + + m = mask >> (63 - shift); + if (rnat1_kaddr >= kbsp) + rnat1 = sw->ar_rnat; + else if (rnat1_kaddr > krbs) + rnat1 = *rnat1_kaddr; + urnat |= (rnat1 & m) << (63 - shift); + return urnat; +} + +/* + * The reverse of get_rnat. + */ +static void +put_rnat (struct task_struct *task, struct switch_stack *sw, + unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat, + unsigned long *urbs_end) +{ + unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m; + unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift; + long num_regs, nbits; + struct pt_regs *pt; + unsigned long cfm, *urbs_kargs; + + pt = ia64_task_regs(task); + kbsp = (unsigned long *) sw->ar_bspstore; + ubspstore = (unsigned long *) pt->ar_bspstore; + + urbs_kargs = urbs_end; + if (in_syscall(pt)) { + /* + * If entered via syscall, don't allow user to set rnat bits + * for syscall args. + */ + cfm = pt->cr_ifs; + urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f)); + } + + if (urbs_kargs >= urnat_addr) + nbits = 63; + else { + if ((urnat_addr - 63) >= urbs_kargs) + return; + nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs); + } + mask = MASK(nbits); + + /* + * First, figure out which bit number slot 0 in user-land maps + * to in the kernel rnat. Do this by figuring out how many + * register slots we're beyond the user's backingstore and + * then computing the equivalent address in kernel space. + */ + num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1); + slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs); + shift = ia64_rse_slot_num(slot0_kaddr); + rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr); + rnat0_kaddr = rnat1_kaddr - 64; + + if (ubspstore + 63 > urnat_addr) { + /* some bits need to be place in pt->ar_rnat: */ + umask = MASK(ia64_rse_slot_num(ubspstore)) & mask; + pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask); + mask &= ~umask; + if (!mask) + return; + } + /* + * Note: Section 11.1 of the EAS guarantees that bit 63 of an + * rnat slot is ignored. so we don't have to clear it here. + */ + rnat0 = (urnat << shift); + m = mask << shift; + if (rnat0_kaddr >= kbsp) + sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m); + else if (rnat0_kaddr > krbs) + *rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m)); + + rnat1 = (urnat >> (63 - shift)); + m = mask >> (63 - shift); + if (rnat1_kaddr >= kbsp) + sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m); + else if (rnat1_kaddr > krbs) + *rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m)); +} + +static inline int +on_kernel_rbs (unsigned long addr, unsigned long bspstore, + unsigned long urbs_end) +{ + unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *) + urbs_end); + return (addr >= bspstore && addr <= (unsigned long) rnat_addr); +} + +/* + * Read a word from the user-level backing store of task CHILD. ADDR + * is the user-level address to read the word from, VAL a pointer to + * the return value, and USER_BSP gives the end of the user-level + * backing store (i.e., it's the address that would be in ar.bsp after + * the user executed a "cover" instruction). + * + * This routine takes care of accessing the kernel register backing + * store for those registers that got spilled there. It also takes + * care of calculating the appropriate RNaT collection words. + */ +long +ia64_peek (struct task_struct *child, struct switch_stack *child_stack, + unsigned long user_rbs_end, unsigned long addr, long *val) +{ + unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr; + struct pt_regs *child_regs; + size_t copied; + long ret; + + urbs_end = (long *) user_rbs_end; + laddr = (unsigned long *) addr; + child_regs = ia64_task_regs(child); + bspstore = (unsigned long *) child_regs->ar_bspstore; + krbs = (unsigned long *) child + IA64_RBS_OFFSET/8; + if (on_kernel_rbs(addr, (unsigned long) bspstore, + (unsigned long) urbs_end)) + { + /* + * Attempt to read the RBS in an area that's actually + * on the kernel RBS => read the corresponding bits in + * the kernel RBS. + */ + rnat_addr = ia64_rse_rnat_addr(laddr); + ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end); + + if (laddr == rnat_addr) { + /* return NaT collection word itself */ + *val = ret; + return 0; + } + + if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) { + /* + * It is implementation dependent whether the + * data portion of a NaT value gets saved on a + * st8.spill or RSE spill (e.g., see EAS 2.6, + * 4.4.4.6 Register Spill and Fill). To get + * consistent behavior across all possible + * IA-64 implementations, we return zero in + * this case. + */ + *val = 0; + return 0; + } + + if (laddr < urbs_end) { + /* + * The desired word is on the kernel RBS and + * is not a NaT. + */ + regnum = ia64_rse_num_regs(bspstore, laddr); + *val = *ia64_rse_skip_regs(krbs, regnum); + return 0; + } + } + copied = access_process_vm(child, addr, &ret, sizeof(ret), 0); + if (copied != sizeof(ret)) + return -EIO; + *val = ret; + return 0; +} + +long +ia64_poke (struct task_struct *child, struct switch_stack *child_stack, + unsigned long user_rbs_end, unsigned long addr, long val) +{ + unsigned long *bspstore, *krbs, regnum, *laddr; + unsigned long *urbs_end = (long *) user_rbs_end; + struct pt_regs *child_regs; + + laddr = (unsigned long *) addr; + child_regs = ia64_task_regs(child); + bspstore = (unsigned long *) child_regs->ar_bspstore; + krbs = (unsigned long *) child + IA64_RBS_OFFSET/8; + if (on_kernel_rbs(addr, (unsigned long) bspstore, + (unsigned long) urbs_end)) + { + /* + * Attempt to write the RBS in an area that's actually + * on the kernel RBS => write the corresponding bits + * in the kernel RBS. + */ + if (ia64_rse_is_rnat_slot(laddr)) + put_rnat(child, child_stack, krbs, laddr, val, + urbs_end); + else { + if (laddr < urbs_end) { + regnum = ia64_rse_num_regs(bspstore, laddr); + *ia64_rse_skip_regs(krbs, regnum) = val; + } + } + } else if (access_process_vm(child, addr, &val, sizeof(val), 1) + != sizeof(val)) + return -EIO; + return 0; +} + +/* + * Calculate the address of the end of the user-level register backing + * store. This is the address that would have been stored in ar.bsp + * if the user had executed a "cover" instruction right before + * entering the kernel. If CFMP is not NULL, it is used to return the + * "current frame mask" that was active at the time the kernel was + * entered. + */ +unsigned long +ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt, + unsigned long *cfmp) +{ + unsigned long *krbs, *bspstore, cfm = pt->cr_ifs; + long ndirty; + + krbs = (unsigned long *) child + IA64_RBS_OFFSET/8; + bspstore = (unsigned long *) pt->ar_bspstore; + ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19)); + + if (in_syscall(pt)) + ndirty += (cfm & 0x7f); + else + cfm &= ~(1UL << 63); /* clear valid bit */ + + if (cfmp) + *cfmp = cfm; + return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty); +} + +/* + * Synchronize (i.e, write) the RSE backing store living in kernel + * space to the VM of the CHILD task. SW and PT are the pointers to + * the switch_stack and pt_regs structures, respectively. + * USER_RBS_END is the user-level address at which the backing store + * ends. + */ +long +ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw, + unsigned long user_rbs_start, unsigned long user_rbs_end) +{ + unsigned long addr, val; + long ret; + + /* now copy word for word from kernel rbs to user rbs: */ + for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) { + ret = ia64_peek(child, sw, user_rbs_end, addr, &val); + if (ret < 0) + return ret; + if (access_process_vm(child, addr, &val, sizeof(val), 1) + != sizeof(val)) + return -EIO; + } + return 0; +} + +static inline int +thread_matches (struct task_struct *thread, unsigned long addr) +{ + unsigned long thread_rbs_end; + struct pt_regs *thread_regs; + + if (ptrace_check_attach(thread, 0) < 0) + /* + * If the thread is not in an attachable state, we'll + * ignore it. The net effect is that if ADDR happens + * to overlap with the portion of the thread's + * register backing store that is currently residing + * on the thread's kernel stack, then ptrace() may end + * up accessing a stale value. But if the thread + * isn't stopped, that's a problem anyhow, so we're + * doing as well as we can... + */ + return 0; + + thread_regs = ia64_task_regs(thread); + thread_rbs_end = ia64_get_user_rbs_end(thread, thread_regs, NULL); + if (!on_kernel_rbs(addr, thread_regs->ar_bspstore, thread_rbs_end)) + return 0; + + return 1; /* looks like we've got a winner */ +} + +/* + * GDB apparently wants to be able to read the register-backing store + * of any thread when attached to a given process. If we are peeking + * or poking an address that happens to reside in the kernel-backing + * store of another thread, we need to attach to that thread, because + * otherwise we end up accessing stale data. + * + * task_list_lock must be read-locked before calling this routine! + */ +static struct task_struct * +find_thread_for_addr (struct task_struct *child, unsigned long addr) +{ + struct task_struct *g, *p; + struct mm_struct *mm; + int mm_users; + + if (!(mm = get_task_mm(child))) + return child; + + /* -1 because of our get_task_mm(): */ + mm_users = atomic_read(&mm->mm_users) - 1; + if (mm_users <= 1) + goto out; /* not multi-threaded */ + + /* + * First, traverse the child's thread-list. Good for scalability with + * NPTL-threads. + */ + p = child; + do { + if (thread_matches(p, addr)) { + child = p; + goto out; + } + if (mm_users-- <= 1) + goto out; + } while ((p = next_thread(p)) != child); + + do_each_thread(g, p) { + if (child->mm != mm) + continue; + + if (thread_matches(p, addr)) { + child = p; + goto out; + } + } while_each_thread(g, p); + out: + mmput(mm); + return child; +} + +/* + * Write f32-f127 back to task->thread.fph if it has been modified. + */ +inline void +ia64_flush_fph (struct task_struct *task) +{ + struct ia64_psr *psr = ia64_psr(ia64_task_regs(task)); + + if (ia64_is_local_fpu_owner(task) && psr->mfh) { + psr->mfh = 0; + task->thread.flags |= IA64_THREAD_FPH_VALID; + ia64_save_fpu(&task->thread.fph[0]); + } +} + +/* + * Sync the fph state of the task so that it can be manipulated + * through thread.fph. If necessary, f32-f127 are written back to + * thread.fph or, if the fph state hasn't been used before, thread.fph + * is cleared to zeroes. Also, access to f32-f127 is disabled to + * ensure that the task picks up the state from thread.fph when it + * executes again. + */ +void +ia64_sync_fph (struct task_struct *task) +{ + struct ia64_psr *psr = ia64_psr(ia64_task_regs(task)); + + ia64_flush_fph(task); + if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) { + task->thread.flags |= IA64_THREAD_FPH_VALID; + memset(&task->thread.fph, 0, sizeof(task->thread.fph)); + } + ia64_drop_fpu(task); + psr->dfh = 1; +} + +static int +access_fr (struct unw_frame_info *info, int regnum, int hi, + unsigned long *data, int write_access) +{ + struct ia64_fpreg fpval; + int ret; + + ret = unw_get_fr(info, regnum, &fpval); + if (ret < 0) + return ret; + + if (write_access) { + fpval.u.bits[hi] = *data; + ret = unw_set_fr(info, regnum, fpval); + } else + *data = fpval.u.bits[hi]; + return ret; +} + +/* + * Change the machine-state of CHILD such that it will return via the normal + * kernel exit-path, rather than the syscall-exit path. + */ +static void +convert_to_non_syscall (struct task_struct *child, struct pt_regs *pt, + unsigned long cfm) +{ + struct unw_frame_info info, prev_info; + unsigned long ip, pr; + + unw_init_from_blocked_task(&info, child); + while (1) { + prev_info = info; + if (unw_unwind(&info) < 0) + return; + if (unw_get_rp(&info, &ip) < 0) + return; + if (ip < FIXADDR_USER_END) + break; + } + + unw_get_pr(&prev_info, &pr); + pr &= ~(1UL << PRED_SYSCALL); + pr |= (1UL << PRED_NON_SYSCALL); + unw_set_pr(&prev_info, pr); + + pt->cr_ifs = (1UL << 63) | cfm; +} + +static int +access_nat_bits (struct task_struct *child, struct pt_regs *pt, + struct unw_frame_info *info, + unsigned long *data, int write_access) +{ + unsigned long regnum, nat_bits, scratch_unat, dummy = 0; + char nat = 0; + + if (write_access) { + nat_bits = *data; + scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits); + if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) { + dprintk("ptrace: failed to set ar.unat\n"); + return -1; + } + for (regnum = 4; regnum <= 7; ++regnum) { + unw_get_gr(info, regnum, &dummy, &nat); + unw_set_gr(info, regnum, dummy, + (nat_bits >> regnum) & 1); + } + } else { + if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) { + dprintk("ptrace: failed to read ar.unat\n"); + return -1; + } + nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat); + for (regnum = 4; regnum <= 7; ++regnum) { + unw_get_gr(info, regnum, &dummy, &nat); + nat_bits |= (nat != 0) << regnum; + } + *data = nat_bits; + } + return 0; +} + +static int +access_uarea (struct task_struct *child, unsigned long addr, + unsigned long *data, int write_access) +{ + unsigned long *ptr, regnum, urbs_end, rnat_addr, cfm; + struct switch_stack *sw; + struct pt_regs *pt; +# define pt_reg_addr(pt, reg) ((void *) \ + ((unsigned long) (pt) \ + + offsetof(struct pt_regs, reg))) + + + pt = ia64_task_regs(child); + sw = (struct switch_stack *) (child->thread.ksp + 16); + + if ((addr & 0x7) != 0) { + dprintk("ptrace: unaligned register address 0x%lx\n", addr); + return -1; + } + + if (addr < PT_F127 + 16) { + /* accessing fph */ + if (write_access) + ia64_sync_fph(child); + else + ia64_flush_fph(child); + ptr = (unsigned long *) + ((unsigned long) &child->thread.fph + addr); + } else if ((addr >= PT_F10) && (addr < PT_F11 + 16)) { + /* scratch registers untouched by kernel (saved in pt_regs) */ + ptr = pt_reg_addr(pt, f10) + (addr - PT_F10); + } else if (addr >= PT_F12 && addr < PT_F15 + 16) { + /* + * Scratch registers untouched by kernel (saved in + * switch_stack). + */ + ptr = (unsigned long *) ((long) sw + + (addr - PT_NAT_BITS - 32)); + } else if (addr < PT_AR_LC + 8) { + /* preserved state: */ + struct unw_frame_info info; + char nat = 0; + int ret; + + unw_init_from_blocked_task(&info, child); + if (unw_unwind_to_user(&info) < 0) + return -1; + + switch (addr) { + case PT_NAT_BITS: + return access_nat_bits(child, pt, &info, + data, write_access); + + case PT_R4: case PT_R5: case PT_R6: case PT_R7: + if (write_access) { + /* read NaT bit first: */ + unsigned long dummy; + + ret = unw_get_gr(&info, (addr - PT_R4)/8 + 4, + &dummy, &nat); + if (ret < 0) + return ret; + } + return unw_access_gr(&info, (addr - PT_R4)/8 + 4, data, + &nat, write_access); + + case PT_B1: case PT_B2: case PT_B3: + case PT_B4: case PT_B5: + return unw_access_br(&info, (addr - PT_B1)/8 + 1, data, + write_access); + + case PT_AR_EC: + return unw_access_ar(&info, UNW_AR_EC, data, + write_access); + + case PT_AR_LC: + return unw_access_ar(&info, UNW_AR_LC, data, + write_access); + + default: + if (addr >= PT_F2 && addr < PT_F5 + 16) + return access_fr(&info, (addr - PT_F2)/16 + 2, + (addr & 8) != 0, data, + write_access); + else if (addr >= PT_F16 && addr < PT_F31 + 16) + return access_fr(&info, + (addr - PT_F16)/16 + 16, + (addr & 8) != 0, + data, write_access); + else { + dprintk("ptrace: rejecting access to register " + "address 0x%lx\n", addr); + return -1; + } + } + } else if (addr < PT_F9+16) { + /* scratch state */ + switch (addr) { + case PT_AR_BSP: + /* + * By convention, we use PT_AR_BSP to refer to + * the end of the user-level backing store. + * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof) + * to get the real value of ar.bsp at the time + * the kernel was entered. + * + * Furthermore, when changing the contents of + * PT_AR_BSP (or PT_CFM) we MUST copy any + * users-level stacked registers that are + * stored on the kernel stack back to + * user-space because otherwise, we might end + * up clobbering kernel stacked registers. + * Also, if this happens while the task is + * blocked in a system call, which convert the + * state such that the non-system-call exit + * path is used. This ensures that the proper + * state will be picked up when resuming + * execution. However, it *also* means that + * once we write PT_AR_BSP/PT_CFM, it won't be + * possible to modify the syscall arguments of + * the pending system call any longer. This + * shouldn't be an issue because modifying + * PT_AR_BSP/PT_CFM generally implies that + * we're either abandoning the pending system + * call or that we defer it's re-execution + * (e.g., due to GDB doing an inferior + * function call). + */ + urbs_end = ia64_get_user_rbs_end(child, pt, &cfm); + if (write_access) { + if (*data != urbs_end) { + if (ia64_sync_user_rbs(child, sw, + pt->ar_bspstore, + urbs_end) < 0) + return -1; + if (in_syscall(pt)) + convert_to_non_syscall(child, + pt, + cfm); + /* + * Simulate user-level write + * of ar.bsp: + */ + pt->loadrs = 0; + pt->ar_bspstore = *data; + } + } else + *data = urbs_end; + return 0; + + case PT_CFM: + urbs_end = ia64_get_user_rbs_end(child, pt, &cfm); + if (write_access) { + if (((cfm ^ *data) & PFM_MASK) != 0) { + if (ia64_sync_user_rbs(child, sw, + pt->ar_bspstore, + urbs_end) < 0) + return -1; + if (in_syscall(pt)) + convert_to_non_syscall(child, + pt, + cfm); + pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK) + | (*data & PFM_MASK)); + } + } else + *data = cfm; + return 0; + + case PT_CR_IPSR: + if (write_access) + pt->cr_ipsr = ((*data & IPSR_MASK) + | (pt->cr_ipsr & ~IPSR_MASK)); + else + *data = (pt->cr_ipsr & IPSR_MASK); + return 0; + + case PT_AR_RNAT: + urbs_end = ia64_get_user_rbs_end(child, pt, NULL); + rnat_addr = (long) ia64_rse_rnat_addr((long *) + urbs_end); + if (write_access) + return ia64_poke(child, sw, urbs_end, + rnat_addr, *data); + else + return ia64_peek(child, sw, urbs_end, + rnat_addr, data); + + case PT_R1: + ptr = pt_reg_addr(pt, r1); + break; + case PT_R2: case PT_R3: + ptr = pt_reg_addr(pt, r2) + (addr - PT_R2); + break; + case PT_R8: case PT_R9: case PT_R10: case PT_R11: + ptr = pt_reg_addr(pt, r8) + (addr - PT_R8); + break; + case PT_R12: case PT_R13: + ptr = pt_reg_addr(pt, r12) + (addr - PT_R12); + break; + case PT_R14: + ptr = pt_reg_addr(pt, r14); + break; + case PT_R15: + ptr = pt_reg_addr(pt, r15); + break; + case PT_R16: case PT_R17: case PT_R18: case PT_R19: + case PT_R20: case PT_R21: case PT_R22: case PT_R23: + case PT_R24: case PT_R25: case PT_R26: case PT_R27: + case PT_R28: case PT_R29: case PT_R30: case PT_R31: + ptr = pt_reg_addr(pt, r16) + (addr - PT_R16); + break; + case PT_B0: + ptr = pt_reg_addr(pt, b0); + break; + case PT_B6: + ptr = pt_reg_addr(pt, b6); + break; + case PT_B7: + ptr = pt_reg_addr(pt, b7); + break; + case PT_F6: case PT_F6+8: case PT_F7: case PT_F7+8: + case PT_F8: case PT_F8+8: case PT_F9: case PT_F9+8: + ptr = pt_reg_addr(pt, f6) + (addr - PT_F6); + break; + case PT_AR_BSPSTORE: + ptr = pt_reg_addr(pt, ar_bspstore); + break; + case PT_AR_RSC: + ptr = pt_reg_addr(pt, ar_rsc); + break; + case PT_AR_UNAT: + ptr = pt_reg_addr(pt, ar_unat); + break; + case PT_AR_PFS: + ptr = pt_reg_addr(pt, ar_pfs); + break; + case PT_AR_CCV: + ptr = pt_reg_addr(pt, ar_ccv); + break; + case PT_AR_FPSR: + ptr = pt_reg_addr(pt, ar_fpsr); + break; + case PT_CR_IIP: + ptr = pt_reg_addr(pt, cr_iip); + break; + case PT_PR: + ptr = pt_reg_addr(pt, pr); + break; + /* scratch register */ + + default: + /* disallow accessing anything else... */ + dprintk("ptrace: rejecting access to register " + "address 0x%lx\n", addr); + return -1; + } + } else if (addr <= PT_AR_SSD) { + ptr = pt_reg_addr(pt, ar_csd) + (addr - PT_AR_CSD); + } else { + /* access debug registers */ + + if (addr >= PT_IBR) { + regnum = (addr - PT_IBR) >> 3; + ptr = &child->thread.ibr[0]; + } else { + regnum = (addr - PT_DBR) >> 3; + ptr = &child->thread.dbr[0]; + } + + if (regnum >= 8) { + dprintk("ptrace: rejecting access to register " + "address 0x%lx\n", addr); + return -1; + } +#ifdef CONFIG_PERFMON + /* + * Check if debug registers are used by perfmon. This + * test must be done once we know that we can do the + * operation, i.e. the arguments are all valid, but + * before we start modifying the state. + * + * Perfmon needs to keep a count of how many processes + * are trying to modify the debug registers for system + * wide monitoring sessions. + * + * We also include read access here, because they may + * cause the PMU-installed debug register state + * (dbr[], ibr[]) to be reset. The two arrays are also + * used by perfmon, but we do not use + * IA64_THREAD_DBG_VALID. The registers are restored + * by the PMU context switch code. + */ + if (pfm_use_debug_registers(child)) return -1; +#endif + + if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) { + child->thread.flags |= IA64_THREAD_DBG_VALID; + memset(child->thread.dbr, 0, + sizeof(child->thread.dbr)); + memset(child->thread.ibr, 0, + sizeof(child->thread.ibr)); + } + + ptr += regnum; + + if ((regnum & 1) && write_access) { + /* don't let the user set kernel-level breakpoints: */ + *ptr = *data & ~(7UL << 56); + return 0; + } + } + if (write_access) + *ptr = *data; + else + *data = *ptr; + return 0; +} + +static long +ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr) +{ + unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val; + struct unw_frame_info info; + struct ia64_fpreg fpval; + struct switch_stack *sw; + struct pt_regs *pt; + long ret, retval = 0; + char nat = 0; + int i; + + if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs))) + return -EIO; + + pt = ia64_task_regs(child); + sw = (struct switch_stack *) (child->thread.ksp + 16); + unw_init_from_blocked_task(&info, child); + if (unw_unwind_to_user(&info) < 0) { + return -EIO; + } + + if (((unsigned long) ppr & 0x7) != 0) { + dprintk("ptrace:unaligned register address %p\n", ppr); + return -EIO; + } + + if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0 + || access_uarea(child, PT_AR_EC, &ec, 0) < 0 + || access_uarea(child, PT_AR_LC, &lc, 0) < 0 + || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0 + || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0 + || access_uarea(child, PT_CFM, &cfm, 0) + || access_uarea(child, PT_NAT_BITS, &nat_bits, 0)) + return -EIO; + + /* control regs */ + + retval |= __put_user(pt->cr_iip, &ppr->cr_iip); + retval |= __put_user(psr, &ppr->cr_ipsr); + + /* app regs */ + + retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]); + retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]); + retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]); + retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]); + retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]); + retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]); + + retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]); + retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]); + retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]); + retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]); + retval |= __put_user(cfm, &ppr->cfm); + + /* gr1-gr3 */ + + retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long)); + retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2); + + /* gr4-gr7 */ + + for (i = 4; i < 8; i++) { + if (unw_access_gr(&info, i, &val, &nat, 0) < 0) + return -EIO; + retval |= __put_user(val, &ppr->gr[i]); + } + + /* gr8-gr11 */ + + retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4); + + /* gr12-gr15 */ + + retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2); + retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long)); + retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long)); + + /* gr16-gr31 */ + + retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16); + + /* b0 */ + + retval |= __put_user(pt->b0, &ppr->br[0]); + + /* b1-b5 */ + + for (i = 1; i < 6; i++) { + if (unw_access_br(&info, i, &val, 0) < 0) + return -EIO; + __put_user(val, &ppr->br[i]); + } + + /* b6-b7 */ + + retval |= __put_user(pt->b6, &ppr->br[6]); + retval |= __put_user(pt->b7, &ppr->br[7]); + + /* fr2-fr5 */ + + for (i = 2; i < 6; i++) { + if (unw_get_fr(&info, i, &fpval) < 0) + return -EIO; + retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval)); + } + + /* fr6-fr11 */ + + retval |= __copy_to_user(&ppr->fr[6], &pt->f6, + sizeof(struct ia64_fpreg) * 6); + + /* fp scratch regs(12-15) */ + + retval |= __copy_to_user(&ppr->fr[12], &sw->f12, + sizeof(struct ia64_fpreg) * 4); + + /* fr16-fr31 */ + + for (i = 16; i < 32; i++) { + if (unw_get_fr(&info, i, &fpval) < 0) + return -EIO; + retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval)); + } + + /* fph */ + + ia64_flush_fph(child); + retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph, + sizeof(ppr->fr[32]) * 96); + + /* preds */ + + retval |= __put_user(pt->pr, &ppr->pr); + + /* nat bits */ + + retval |= __put_user(nat_bits, &ppr->nat); + + ret = retval ? -EIO : 0; + return ret; +} + +static long +ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr) +{ + unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val = 0; + struct unw_frame_info info; + struct switch_stack *sw; + struct ia64_fpreg fpval; + struct pt_regs *pt; + long ret, retval = 0; + int i; + + memset(&fpval, 0, sizeof(fpval)); + + if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs))) + return -EIO; + + pt = ia64_task_regs(child); + sw = (struct switch_stack *) (child->thread.ksp + 16); + unw_init_from_blocked_task(&info, child); + if (unw_unwind_to_user(&info) < 0) { + return -EIO; + } + + if (((unsigned long) ppr & 0x7) != 0) { + dprintk("ptrace:unaligned register address %p\n", ppr); + return -EIO; + } + + /* control regs */ + + retval |= __get_user(pt->cr_iip, &ppr->cr_iip); + retval |= __get_user(psr, &ppr->cr_ipsr); + + /* app regs */ + + retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]); + retval |= __get_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]); + retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]); + retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]); + retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]); + retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]); + + retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]); + retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]); + retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]); + retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]); + retval |= __get_user(cfm, &ppr->cfm); + + /* gr1-gr3 */ + + retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long)); + retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2); + + /* gr4-gr7 */ + + for (i = 4; i < 8; i++) { + retval |= __get_user(val, &ppr->gr[i]); + /* NaT bit will be set via PT_NAT_BITS: */ + if (unw_set_gr(&info, i, val, 0) < 0) + return -EIO; + } + + /* gr8-gr11 */ + + retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4); + + /* gr12-gr15 */ + + retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2); + retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long)); + retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long)); + + /* gr16-gr31 */ + + retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16); + + /* b0 */ + + retval |= __get_user(pt->b0, &ppr->br[0]); + + /* b1-b5 */ + + for (i = 1; i < 6; i++) { + retval |= __get_user(val, &ppr->br[i]); + unw_set_br(&info, i, val); + } + + /* b6-b7 */ + + retval |= __get_user(pt->b6, &ppr->br[6]); + retval |= __get_user(pt->b7, &ppr->br[7]); + + /* fr2-fr5 */ + + for (i = 2; i < 6; i++) { + retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval)); + if (unw_set_fr(&info, i, fpval) < 0) + return -EIO; + } + + /* fr6-fr11 */ + + retval |= __copy_from_user(&pt->f6, &ppr->fr[6], + sizeof(ppr->fr[6]) * 6); + + /* fp scratch regs(12-15) */ + + retval |= __copy_from_user(&sw->f12, &ppr->fr[12], + sizeof(ppr->fr[12]) * 4); + + /* fr16-fr31 */ + + for (i = 16; i < 32; i++) { + retval |= __copy_from_user(&fpval, &ppr->fr[i], + sizeof(fpval)); + if (unw_set_fr(&info, i, fpval) < 0) + return -EIO; + } + + /* fph */ + + ia64_sync_fph(child); + retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32], + sizeof(ppr->fr[32]) * 96); + + /* preds */ + + retval |= __get_user(pt->pr, &ppr->pr); + + /* nat bits */ + + retval |= __get_user(nat_bits, &ppr->nat); + + retval |= access_uarea(child, PT_CR_IPSR, &psr, 1); + retval |= access_uarea(child, PT_AR_EC, &ec, 1); + retval |= access_uarea(child, PT_AR_LC, &lc, 1); + retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1); + retval |= access_uarea(child, PT_AR_BSP, &bsp, 1); + retval |= access_uarea(child, PT_CFM, &cfm, 1); + retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1); + + ret = retval ? -EIO : 0; + return ret; +} + +/* + * Called by kernel/ptrace.c when detaching.. + * + * Make sure the single step bit is not set. + */ +void +ptrace_disable (struct task_struct *child) +{ + struct ia64_psr *child_psr = ia64_psr(ia64_task_regs(child)); + + /* make sure the single step/taken-branch trap bits are not set: */ + child_psr->ss = 0; + child_psr->tb = 0; +} + +asmlinkage long +sys_ptrace (long request, pid_t pid, unsigned long addr, unsigned long data) +{ + struct pt_regs *pt; + unsigned long urbs_end, peek_or_poke; + struct task_struct *child; + struct switch_stack *sw; + long ret; + + lock_kernel(); + ret = -EPERM; + if (request == PTRACE_TRACEME) { + /* are we already being traced? */ + if (current->ptrace & PT_PTRACED) + goto out; + ret = security_ptrace(current->parent, current); + if (ret) + goto out; + current->ptrace |= PT_PTRACED; + ret = 0; + goto out; + } + + peek_or_poke = (request == PTRACE_PEEKTEXT + || request == PTRACE_PEEKDATA + || request == PTRACE_POKETEXT + || request == PTRACE_POKEDATA); + ret = -ESRCH; + read_lock(&tasklist_lock); + { + child = find_task_by_pid(pid); + if (child) { + if (peek_or_poke) + child = find_thread_for_addr(child, addr); + get_task_struct(child); + } + } + read_unlock(&tasklist_lock); + if (!child) + goto out; + ret = -EPERM; + if (pid == 1) /* no messing around with init! */ + goto out_tsk; + + if (request == PTRACE_ATTACH) { + ret = ptrace_attach(child); + goto out_tsk; + } + + ret = ptrace_check_attach(child, request == PTRACE_KILL); + if (ret < 0) + goto out_tsk; + + pt = ia64_task_regs(child); + sw = (struct switch_stack *) (child->thread.ksp + 16); + + switch (request) { + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: + /* read word at location addr */ + urbs_end = ia64_get_user_rbs_end(child, pt, NULL); + ret = ia64_peek(child, sw, urbs_end, addr, &data); + if (ret == 0) { + ret = data; + /* ensure "ret" is not mistaken as an error code: */ + force_successful_syscall_return(); + } + goto out_tsk; + + case PTRACE_POKETEXT: + case PTRACE_POKEDATA: + /* write the word at location addr */ + urbs_end = ia64_get_user_rbs_end(child, pt, NULL); + ret = ia64_poke(child, sw, urbs_end, addr, data); + goto out_tsk; + + case PTRACE_PEEKUSR: + /* read the word at addr in the USER area */ + if (access_uarea(child, addr, &data, 0) < 0) { + ret = -EIO; + goto out_tsk; + } + ret = data; + /* ensure "ret" is not mistaken as an error code */ + force_successful_syscall_return(); + goto out_tsk; + + case PTRACE_POKEUSR: + /* write the word at addr in the USER area */ + if (access_uarea(child, addr, &data, 1) < 0) { + ret = -EIO; + goto out_tsk; + } + ret = 0; + goto out_tsk; + + case PTRACE_OLD_GETSIGINFO: + /* for backwards-compatibility */ + ret = ptrace_request(child, PTRACE_GETSIGINFO, addr, data); + goto out_tsk; + + case PTRACE_OLD_SETSIGINFO: + /* for backwards-compatibility */ + ret = ptrace_request(child, PTRACE_SETSIGINFO, addr, data); + goto out_tsk; + + case PTRACE_SYSCALL: + /* continue and stop at next (return from) syscall */ + case PTRACE_CONT: + /* restart after signal. */ + ret = -EIO; + if (data > _NSIG) + goto out_tsk; + if (request == PTRACE_SYSCALL) + set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + else + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + child->exit_code = data; + + /* + * Make sure the single step/taken-branch trap bits + * are not set: + */ + ia64_psr(pt)->ss = 0; + ia64_psr(pt)->tb = 0; + + wake_up_process(child); + ret = 0; + goto out_tsk; + + case PTRACE_KILL: + /* + * Make the child exit. Best I can do is send it a + * sigkill. Perhaps it should be put in the status + * that it wants to exit. + */ + if (child->exit_state == EXIT_ZOMBIE) + /* already dead */ + goto out_tsk; + child->exit_code = SIGKILL; + + ptrace_disable(child); + wake_up_process(child); + ret = 0; + goto out_tsk; + + case PTRACE_SINGLESTEP: + /* let child execute for one instruction */ + case PTRACE_SINGLEBLOCK: + ret = -EIO; + if (data > _NSIG) + goto out_tsk; + + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + if (request == PTRACE_SINGLESTEP) { + ia64_psr(pt)->ss = 1; + } else { + ia64_psr(pt)->tb = 1; + } + child->exit_code = data; + + /* give it a chance to run. */ + wake_up_process(child); + ret = 0; + goto out_tsk; + + case PTRACE_DETACH: + /* detach a process that was attached. */ + ret = ptrace_detach(child, data); + goto out_tsk; + + case PTRACE_GETREGS: + ret = ptrace_getregs(child, + (struct pt_all_user_regs __user *) data); + goto out_tsk; + + case PTRACE_SETREGS: + ret = ptrace_setregs(child, + (struct pt_all_user_regs __user *) data); + goto out_tsk; + + default: + ret = ptrace_request(child, request, addr, data); + goto out_tsk; + } + out_tsk: + put_task_struct(child); + out: + unlock_kernel(); + return ret; +} + + +void +syscall_trace (void) +{ + if (!test_thread_flag(TIF_SYSCALL_TRACE)) + return; + if (!(current->ptrace & PT_PTRACED)) + return; + /* + * The 0x80 provides a way for the tracing parent to + * distinguish between a syscall stop and SIGTRAP delivery. + */ + ptrace_notify(SIGTRAP + | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0)); + + /* + * This isn't the same as continuing with a signal, but it + * will do for normal use. strace only continues with a + * signal if the stopping signal is not SIGTRAP. -brl + */ + if (current->exit_code) { + send_sig(current->exit_code, current, 1); + current->exit_code = 0; + } +} + +/* "asmlinkage" so the input arguments are preserved... */ + +asmlinkage void +syscall_trace_enter (long arg0, long arg1, long arg2, long arg3, + long arg4, long arg5, long arg6, long arg7, + struct pt_regs regs) +{ + long syscall; + + if (unlikely(current->audit_context)) { + if (IS_IA32_PROCESS(®s)) + syscall = regs.r1; + else + syscall = regs.r15; + + audit_syscall_entry(current, syscall, arg0, arg1, arg2, arg3); + } + + if (test_thread_flag(TIF_SYSCALL_TRACE) + && (current->ptrace & PT_PTRACED)) + syscall_trace(); +} + +/* "asmlinkage" so the input arguments are preserved... */ + +asmlinkage void +syscall_trace_leave (long arg0, long arg1, long arg2, long arg3, + long arg4, long arg5, long arg6, long arg7, + struct pt_regs regs) +{ + if (unlikely(current->audit_context)) + audit_syscall_exit(current, regs.r8); + + if (test_thread_flag(TIF_SYSCALL_TRACE) + && (current->ptrace & PT_PTRACED)) + syscall_trace(); +} |